Textile material and method of making the same



Patented July 13, 1937 UNITED STATES PATENT OFFICE TEXTILE MATERIAL ANDMETHOD OF MAK- Celanese Corporation of America,

of Delaware a corporation No Drawing. Application May 17, 1932, SerialNo. 611,943

12 Claims.

This invention relates to the treatment or preparation of staple fibreswhich are more suitable for spinning or other textile operations.

I An object of my invention is to prepare or treat staple fibres,particularly fibres made of organic derivatives of cellulose with amaterial adapted to destroy or diminish the tendency of such fibres todevelop electrostatic charges when manipulated, so that the staplefibres may be successfully associated together to form spun yarn.

Other objects of my invention will appear from the following detaileddescription.

The formation of spun yarn from comparatively short lengths or staples01' filaments or threads composed of organic derivatives o1 cellulosepresents serious difliculty. This is due to the fact that such organicderivatives of cellulose have a very high di-electric constant and whenthe filaments are rubbed together during the various operations involvedin spinning, a great static charge of electricity is produced. Becauseof the static electrical charge, the staple fibres do not adhere to eachother readily and cause great difiiculty in the spinning operation.

I have found that if a solution of an electrolyte in a solvent ofrelatively high boiling point is applied to or incorporated in staplefibres, the

tendency to generate static electricity during the spinning operation isgreatly reduced. More- 'diificulty encountered in cutting such filamentsto uniform staple lengths is overcome.

In accordance with my invention I prepare staple fibres containing asolution of an electrolyte ina solvent of relatively high boiling point.This solution of electrolyte may be incorporated in relativelycontinuous lengths of artificial filintermediate stage of the spinningoperation or to the spun yarn itself. 1 While this invention is oflulose such as lulose ethers.

organic esters oi cellulose and celmethylamine, methylaminehydrochloride or a mixture of two or more 01' these.

As a solvent for the electroylte I prefer to employ a liquid having arelatively high boiling 40 'ford system, etc. 7 includes thepreliminaryolefine glycols such as the monomethyl ether of ethylene glycol, themono ethyl ether of ethylene glycol or the diethylether of diethyleneglycol. In order to stablize the solution against change of volume,viscosity or concentration due to evaporation or absorption of water, itis preferable to add a quantity or water substantially equal to theamount of water these liquids tend to absorb from the air, the amount ofwater being 30% in the case or diethylene glycol, 13% in the case ofethylene'glycol and'33% in the case of glycerol.

The amount of electrolyte present in the solution and the amount ofsolution appliedwill vary in accordance with the nature of both theelectrolyte and solvent, the nature of the staple fibres and the resultto be obtained. Generally the electrolyte will be present inconcentrations of 1 to 25%, and the amount of solution applied orincorporated in the fibres will be from 1 to 40% of the weight of thefibres.

The filaments or yarns may be treated with the solution of theelectrolyte while they are still in the comparatively continuous lengthsin which they are formed. Conveniently the solution of electrolyte maybe applied bymeans of wicks, rollers or other furnishing devices to theyarns or filaments while they are in transit. A desirable method is toapply the electrolyte solution to the artificial silk immediately afterthey leave the spinning cabinet in which they are formed while on theway to a cutting device which cuts them into staple fibre. A suitablearrangement for cutting the yarn after leaving the spinning machine isshown and described in the U. S. application No. 278,884 filed May 18,1928. If desired, the relatively continuous lengths may be treated inthe form of hanks or other suitable package prior to being cut intostaples or chapp of suitablelength.

Instead of treating the filaments after their formation with thesolution of electrolyte, such solution may be added to or incorporatedin the spinning solution from which said filaments are formed, wherebyfilaments containing such,- solution are formed directly.

Alternatively the staple fibres, either occurring naturally, or cut fromcontinuous lengths of natural silk or artificial filaments may betreated with the solution of electrolyte in which case the staple fibresmay be placed in bags which are immersed in the bath of the solution andwhich for convenience may be tied in bundles prior to immersion in thebath. The treatment of the staple fibres during an intermediate stage ofthe spinning operations such as immediately after lapping, carding,drawing or slubbing is not excluded from this invention.

As to the length of the staples, lengths: ranging from 0.75 to 10" ormore in length are suitable. The artificial filaments may be of anysuitable weight per unit length, s'ay from'l to30' 'deniers or more,examples of which are 1.9, 3.5 or 5.5 denier.

After treatment with the solution of electrolyte, the short lengths offilaments or threads are then subjected to a suitable spinningoperation, such as is used for the spinning of short lengths of naturalsilk, cotton or wool fibres to form threads by any of the well knownsystems, such as the Cotton, the French, the Worsted, the Wool, the-SpunSilk, the Brad- This spinning operation also treatments necessary to Pteg the filaments-or fibres lathe i031! required for the actual operationof twisting them into yarn.

In order further to illustrate. my invention, but without being limitedthereto, the following specific' examples are given.

Example I way to the cutting device, the ends are caused to pass overwicks which furnish 2 to 3% of the weight or the filaments of thefollowing finish:

' a Parts by weight- Diethylene. glycol Water 30 Magnesium chloride 10Application of this finish is conveniently accomplished by contactingthe filaments with hard lamp wicks -which dip into the finish, the wicksbeing positioned at the foot of the spinning cabinets so that thefilaments contact with the finish immediately after they leave thespinning chamber. Cut fibres so produced are substantially free of andresistant to the development of .electrostatic charges and may be spuninto yarn without any difllculty.

Example 11 The process of Example I is repeated with the exception thatthe amount of finish applied is increased to 8% of the weight of thefinish. To accomplish'this, softer wicks of higher capillarity areemployed, or the wicks may be replaced by furnishing rollers dipping ina trough containing the finish and rotating at convenient speeds. Theresults are similar to those obtained in Example I, but the fibres'havea slightly damp handle and a slight scroop which causes better bindingor adhesion between up of the yarn by a spinning process.

It is to be understood that the foregoing detailed description is givenmerely by way of illustration and that many variations maybe madetherein without departing from the spirit of my invention. I

Having described my invention, what" I claim and desire to secure byLetters Patent is:

1. The method of forming prising spinning staple or short lengthsofartificial filaments made of organicderivatives of cellulose, whichfilaments contain a hygroscopic solution comprising an electrolytehaving no deleterious action on the filamentsl and a major proportion ofan alcohol having a boiling point above 100 C.

2. Method of forming spun yarn, which comprises spinning staple orshort'lengths of artificial filaments made of organic derivatives ofcellulose, which filaments contain a solution comprising magnesiumchloride and a major proportion of diethylene glycol.

3. Method of forming spun yarn, which comprises spinning staple or shortlengths of artificial filaments made of cellulose acetate, whichfilaments contain a solution comprising magnesium chloride and a majorproportion of diethylene'glycol. 1

' 4. Method of forming staplefibres comprising extruding a solution ofcellulose acetate through orifices into a setting medium, applying tothe filaments so formed a solution comprising an the fibres in thebuilding spun" yam coma boiling point above C. 8. Relatively shortfibres or filaments made of cellulose acetate containing a hygroscopicsolu- 3 tion containing magneelum 'cl iloride and a major proportion ofan alcohol having a boiling point above 100 C.

WILLIAM WHI'I'EHEAD.

